63 replies to this topic

[Strum Wealh]

Major Tom, on 02 April 2012 - 07:06 AM, said:

I'd like to point out that if a Guass "Rifle" required such immense power draw from the engine, it would generate an ungodly amount of heat (like a PPC), so capacitor are the most 'logical' option (although why they don't have use the same technolgoy for PPCs is unexplanable, unless it is just old cheap technology)

Well, what we know from Gauss Rifles is that such large capacitor banks are highly explosive if hit by enemy fire.
Smaller PPC Capacitors were developed and deployed in 3060; they were not themselves sufficient to power the weapon, but they did add ~50% damage.

Given what hitting the Gauss Rifles' capacitors can do and how much more power a PPC would likely need to be able to impart significant damage at range through an atmosphere, not using such powerful and volatile capacitor banks is arguably a safety decision - the increased heat seems a relatively small price to pay for decreasing the likelihood of a stray shot blowing the whole 'Mech to bits.

Major Tom, on 02 April 2012 - 07:06 AM, said:

I would also like to point out that it isn't a Rifle, a rifle indicates that the barrel has rifling, used to impart spin and prevent tumbling. This is actually counter productive for a high velocity "kinetic energy penetrator" round.

This is a basic coilgun ("Gauss Gun"):

The coils are magnetized when an electrical current passes through them. This draws the (typically ferromagnetic) projectile to them; after the projectile passes through the current coil, the current coil is switched off and the next one is turned on,

Unlike railguns, the armature/projectile and the coils do not need to be in direct physical contact. As such, the design can include a barrel assembly that can include rifling.

Also:

Quote

The APDS was initially the main design of KE penetrator. The logical progression was to make the shot longer and thinner to concentrate the kinetic energy in a smaller area. However a long, thin rod is aerodynamically unstable; it tends to tumble in flight and is less accurate. Traditionally, shells were given stability in flight from the rifling of the gun barrel, which imparts a spin to the round. Up to a certain limit this is effective, but once the projectile's length is more than six or seven times its diameter, rifling becomes less effective. Adding fins like the fletching of an arrow to the base gives the round stability, hence Armour-Piercing Fin-Stabilized Discarding Sabot (APFSDS).

Given that BattleMech armor is essentially a futuristic version of Chobham or Kanchan armor (both of which are more effective against such "long rod penetrators" than the older RHA technology) and that the canon illustrations show relatively stubby projectiles (as opposed to long, thin rods), it seems reasonable to believe that the Gauss rifles are exactly that - rifled Gauss Guns.

[Solis Obscuri]

Major Tom, on 02 April 2012 - 07:06 AM, said:

I'd like to point out that if a Guass "Rifle" required such immense power draw from the engine, it would generate an ungodly amount of heat (like a PPC), so capacitor are the most 'logical' option (although why they don't have use the same technolgoy for PPCs is unexplanable, unless it is just old cheap technology)

I've often wondered the same thing myself - and if the PPCs are drawing power directly off the reactor, I'd expect the lights in the cockpit to dim while firing one, let alone a salvo of 2-4 at once... Unless maybe PPCs are being treated as a "beam" weapon and doing DoT, with a less immediate power draw?

Major Tom, on 02 April 2012 - 07:06 AM, said:

I would also like to point out that it isn't a Rifle, a rifle indicates that the barrel has rifling, used to impart spin and prevent tumbling. This is actually counter productive for a high velocity "kinetic energy penetrator" round.

Spin stabilization isn't necessarily counterproductive for the projectile, it just tends to be really hard on rifled gun barrels to fire projectiles at the kinds of velocities (~1475m/s-1750m/s) used for APDS/APFSDS shells, and smooth bores both support higher muzzle velocities and take longer to wear out. At the velocities Gauss slugs are supposed to travel at, I doubt a rifled barrel would survive even 8 shots before it was reamed smooth, red hot, and distorting out of shape...

[Ant0nm]

So, is the gauss gun a "one shot one kill" weapon? How powerful was it in the previous games? How powerful do you think it will/should be in MWO? Is there a limit on what mech you can put it on? For example could there be a tiny little ol' mech running around with this super powerful weapon? Im new to mechwarrior so I dont have no idea.

[Strum Wealh]

Ant0nm, on 03 April 2012 - 06:23 AM, said:

So, is the gauss gun a "one shot one kill" weapon? How powerful was it in the previous games? How powerful do you think it will/should be in MWO? Is there a limit on what mech you can put it on? For example could there be a tiny little ol' mech running around with this super powerful weapon? Im new to mechwarrior so I dont have no idea.

Normally (that is, according to the BattleTech/MechWarrior canon), the Gauss Rifle is a very powerful (15 units of damage in a single shot) long-range (660 meters) weapon that generates very little heat (1 unit of heat) when fired.

It is also very heavy - the version built in the Inner Sphere weighs 15 (metric) tons (15,000 kg, or about 33,069.34 lbs) for the weapon itself, and each additional (metric) ton of ammunition includes only eight (8) eight (so, each round weighs 125 kg, or about 275.58 lbs).

It is also very expensive - the weapon itself canonically costs 300,000 c-bills (an in-universe currency), and each ton of ammunition costs an additional 20,000 c-bills.

Canonically, the capacitors that power the weapon explode when hit, damaging the 'Mech on which the Gauss Rifle is mounted.

Canonically, any BattleMech can carry one, as long as it has the free tonnage and critical spaces (a measure of internal volume) available.
As an example, the Hollander, a 35-ton BattleMech, has a single Gauss Rifle (with two tons of ammunition) as its primary (and only) ranged weapon.
By contrast, the Thunder Hawk, a 100-ton BattleMech, carries three Gauss Rifles (with two tons of ammunition each) as its primary weapons, with a set of four Medium Lasers as secondary/backup weapons.

In a way, it is like a "sniper rifle for BattleMechs", and was/is typically used as such in previous MechWarrior games.

There are also several variations:
-- the Clans' Gauss Rifle (less weight and bulk, otherwise identical to the IS version)
-- the Inner Sphere's "Silver Bullet Gauss Rifle" (a experimental variation that fires shotgun-like cluster rounds rather than solid slugs)
-- the Inner Sphere's "Light Gauss Rifle" (less weight and bulk, more rounds per ton, and longer range, but less damage per shot)
-- the Inner Sphere's "Heavy Gauss Rifle" (more weight and bulk, fewer rounds per ton, and shorter range, but more damage per shot)
-- the Clans' "Hyper-Assault Gauss Rifle" (fires many small slugs simultaneously; available in HAG-20, HAG-30, and HAG-40 models)
-- the Clans' "Anti-Personnel Gauss Rifle" (much less weight and bulk, many more rounds per ton, and much shorter range and much less damage per shot)

At the point where MWO is set to start (the middle of the year 3049), only the standard Gauss Rifle variations are available to both the Inner Sphere and the Clans.

[Tempest Corvus]

but what if each gauss rifle had induvidual capacitors, then the power plant could charge them up, then the gauss rifles could fire at once when they are all charged.

[DoomsdayArk]

i agree that to a certain point gauss can not fire at the same time because the load on your reactor would be immense as it tried to recharge unless of course you had a big enough reactor that could handle all the pressure but if not it would could be a problem

[Wyzak]

In MechCommander 2 your equipment officer states that the Clan Gauss Rifle can "absolutely, positively take the head off an Atlas" in one shot. For the IS Gauss, he makes a similar statement about the Mad Cat. So in theory, if you had good aim, you could kill a 'mech of any size in one shot by targeting the head with a Clan Gauss Rifle. In practice, this almost never happens.

[EDMW CSN]

Wyzak, on 03 April 2012 - 08:52 AM, said:

In MechCommander 2 your equipment officer states that the Clan Gauss Rifle can "absolutely, positively take the head off an Atlas" in one shot. For the IS Gauss, he makes a similar statement about the Mad Cat. So in theory, if you had good aim, you could kill a 'mech of any size in one shot by targeting the head with a Clan Gauss Rifle. In practice, this almost never happens.

Try shooting then cockpit glass of a moving Atlas. Try it

[CCC Dober]

Given the kinetic energy on both ends of the barrel, it is quite a gamble to fire several gauss at once. Not even the 100t Fafnir, which was specifically built around these weapons, could handle both Heavy Gauss safely at once and ran danger of falling over if it tried to do so IIRC. I'd bet the THawk would have had similar problems firing all three Gauss as well. 4+ Gauss alphas would practically guarantee a knockdown.

[Karel Spaten]

Wyzak, on 03 April 2012 - 08:52 AM, said:

In MechCommander 2 your equipment officer states that the Clan Gauss Rifle can "absolutely, positively take the head off an Atlas" in one shot. For the IS Gauss, he makes a similar statement about the Mad Cat. So in theory, if you had good aim, you could kill a 'mech of any size in one shot by targeting the head with a Clan Gauss Rifle. In practice, this almost never happens.

The pedant in me wants to point out that it happens once in every 36 hits...

[Gregory Twilight]

and yes a gauss rifle round to the head is a bad day for any mech seeing as the gauss does 15 points of damage and the max armor and int a head can have is a total of 12 points...so a gauss will always win no matter what mech your in.

There is a Big trade off using a gauss over like a PPC you get more damage and less heat but you have 8 shots per ton where a PPC can shoot all day as long as it can dump its heat. once a gauss boat uses up his ammo he is a walking target.

Edited by Gregory Twilight, 03 April 2012 - 11:34 AM.

[William Petersen]

Karel Spaten, on 03 April 2012 - 09:34 AM, said:

The pedant in me wants to point out that it happens once in every 36 hits...

Two very important words you're missing: on average.


Also, anything that deals 12 damage (Clan or IS Gauss, Clan ERPPC, maybe some other newfangled 3060 or 3070 tech) can take the head off any mech. Sometimes the damage threshold is lower (mostly on lights and a few mediums) allowing an even wider range of weaponry to decapitate them. It's a bit tricky to land head shots in the sims, though, as the hitbox for a cockpit tends to be very small (for obvious balance reasons).

[Major Tom]

Solis Obscuri, on 02 April 2012 - 05:16 PM, said:

Spin stabilization isn't necessarily counterproductive for the projectile, it just tends to be really hard on rifled gun barrels to fire projectiles at the kinds of velocities (~1475m/s-1750m/s) used for APDS/APFSDS shells, and smooth bores both support higher muzzle velocities and take longer to wear out. At the velocities Gauss slugs are supposed to travel at, I doubt a rifled barrel would survive even 8 shots before it was reamed smooth, red hot, and distorting out of shape...

I thought the issue with spin is momentum. Instead of all the momentum being applied forward, it is also applied to the rotation, which seemed to suggest less penetration, a fin stabilizer avoided that issue. Altough the idea of barrel rifling wear on high velocity weapons sounds reasonable.

[Solis Obscuri]

Major Tom, on 03 April 2012 - 12:25 PM, said:

I thought the issue with spin is momentum. Instead of all the momentum being applied forward, it is also applied to the rotation, which seemed to suggest less penetration, a fin stabilizer avoided that issue. Altough the idea of barrel rifling wear on high velocity weapons sounds reasonable.

Well, the spin wouldn't decrease momentum... I suppose it's possible it might increase the chance of tumbling on a glancing impact, though, which would be bad for a long-rod penetrator. I'm actually not sure whether APFSDS fins impart a spin or not. Of course, the gauss slug isn't described as a long rod, so it may not be so much of an issue.

[Motionless]

Steamroller Stig, on 01 April 2012 - 04:50 PM, said:

that's what capacitors are for, if anything I wish we could add extra capacitors as a component or even ammo so we could fire Gauss rifle rounds like an auto cannon.

Fund it!

[Gerath Tanden]

Don't forget there is already a precedent in the universe for Mechs to carry and fire more than one gauss rifle at a time. The Stone Rhino (Behemoth) and Timber Wolf (Mad Cat) MK.III both carried twin gauss rifles and used them with extreme prejudice.

[Zakatak]

You sure it isn't due to recoil? It's alot of kinetic energy. Gauss rifles fire 125kg slugs at around 2500m/s or so.

KE = 1/2mv^2
0.5 x 125 x 2500^2 = 78.125 Megajoules

That is just muzzle energy though, another half would be directed backwards as recoil. Let's say we have a Vulture C that fires 2 rifles at once (doubling the KE because we have 2 rifles)...

V = [squareroot] (2 x KE) / Mass [/squareroot]
V = [sqrt] (2 x 156.25e6j) / 60000kg [/sqrt]
V = 72.2m/s

So the Vulture would be pushed back at 72.2m/s, assuming it was on a frictionless floor with the gyro turned off.
EDIT: Sorry, I forgot to half the mass, it would be 39.05MJ per gauss, my bad.

Edited by Zakatak, 03 April 2012 - 07:02 PM.

[trycksh0t]

Zakatak, on 03 April 2012 - 06:02 PM, said:

You sure it isn't due to recoil? It's alot of kinetic energy. Gauss rifles fire 125kg slugs at around 2500m/s or so.

KE = 1/2mv^2
0.5 x 125 x 2500^2 = 78.125 Megajoules

That is just muzzle energy though, another half would be directed backwards as recoil. Let's say we have a Vulture C that fires 2 rifles at once (doubling the KE because we have 2 rifles)...

V = [squareroot] (2 x KE) / Mass [/squareroot]
V = [sqrt] (2 x 156.25e6j) / 60000kg [/sqrt]
V = 72.2m/s

So the Vulture would be pushed back at 72.2m/s, assuming it was on a frictionless floor with the gyro turned off.

However, Gauss Rifles (either coil guns or rail guns) do not recoil the same way cannons do, due to the location of the magnets. A standard cannon shell imparts recoil backwards, because the slug is being propelled forward. In Gaussian weapons, the magnetic forces act from the side of the projectile, so the majority of the opposite reaction (recoil) is directed outwards, not backwards.

[Tuborn]

Artgathan, on 01 April 2012 - 05:38 AM, said:

One small feature that I'd like to see implemented concerns gauss rifles. As far as I know, it hasn't played a role in any previous mechwarrior games.

What I'm talking about is that fact that in the novels (I can't say I know if this is also true concerning the TROs) it has been stated several times that mechs cannot fire more than one gauss rifle simultaneously (due to the energy output required to fire both exceeding the energy output of the mech's powerplant). In fact, several mechs are described as attempting to fire two gauss rifles at the same time; but they always end up firing them in succession (this situation occurs when a Clan mech attempts this) even if they pull the triggers at the same time.

It's just a little feature I'd like to see; I know it's not a big deal (I don't know how likely we are to see mechs weilding multiple gauss rifles in this time period), but I think it would be a nice touch.

If this is true then I hope you can set cain fire in each weapon type IE, ERLL both togather, LGR bang bang. I love two extinded range large lasers backed up by two light gauss rifles, add on other whepons if tonage permits.

[Tuborn]

I do belive that time to fire was time to charge capicitors, dischharge for two or more rifles is based on capicitor bank.